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The sinoatrial (SA) node is a group of specialized cells which sit in the wall of the right atrium. The SA node sets the pace of your heart and is therefore called your pacemaker. SA node sets this pace b...
DNA is made of a string of nucleotide bases attached to one another by a peptide bond. A single nucleotide contains three regions: A phosphate group, a Carboxyl group and a base. Adjacent nucleotides atta...
Planting just one crop such as palm oil in an area decreases biodiversity, resulting in fewer niches for insects. This means that there are fewer insect species in the area, and therefore fewer food sourc...
The diaphragm contacts and moves down. The intercostal muscles between the ribs contract. This causes the ribcage and the sternum to move up and out. The thorax increases in width from back to front. This...
The diaphragm contracts and flattens out, increasing the volume of the thorax and decreasing the pressure in there. This causes a pressure gradient between the thorax and the outside air, so air flows int...
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